Text of my ‘When Worlds Collide’ column published in Ceylon Today newspaper on 29 August 2014
Progress is slow and incremental. Those who take all-or-nothing positions often end up with…nothing.
So let’s hail Sri Lanka’s leading petroleum distributor introducing a super diesel with lower levels of sulphur. This is indeed good news. But much more remains to be done.
Until now, Super Diesel marketed by the state-owned Ceylon Petroleum Corporation (CPC) had a sulphur content of 500 ppm (parts per million). From 22 August 2014, its sulphur has come down to 10 ppm.
“CPC is compelled to improve the quality of diesel, since it contributes a lot towards the reduction of harmful diesel exhaust emissions causing environmental pollution and serious health hazards which have been reported to have costly effects both economically and socially on the society at large,” a media statement said.
A newspaper advertisement from CPC, meanwhile, says ‘Lanka Super Diesel 4 Star’ will be available from ‘selected filling stations islandwide’.
But before rejoicing too much, let’s remember that potential impact of this measure is rather limited.
“Usage of super diesel is very low, perhaps less than 10% (of total diesel consumption),” says Professor Oliver Ileperuma of the University of Peradeniya, who has been studying air quality in Sri Lanka for many years. “I don’t have the exact figures [but] this will not make any change in air pollution levels unless normal diesel too has low sulphur.”
Petroleum Industries Minister Anura Priyadarshana Yapa was recently quoted in the media as saying that CPC also hopes to improve normal diesel (currently with sulphur levels of 2,500 ppm), by replacing it with a diesel with sulphur levels of 1,000 ppm. The timeframe for that switch was not disclosed.
In Sri Lanka, transport is the biggest contributor of air pollution, responsible for around 60% of total pollutants. This results from a combination of low fuel quality, traffic congestion, rising number of vehicles and poor engine maintenance.
Environmental scientists and public health officials have long known that diesel is the deadlier fuel: on average, a diesel car can emit seven times more air toxics than petrol cars of comparable engine power.
In Sri Lanka, diesel vehicles made up nearly half (45%) of the total fleet by end 2010, according to data compiled by the Centre for Science and Environment (CSE), a Delhi-based research and advocacy group. These contributed a disproportionately higher pollution load from the transport sector — nearly all (96%) sulphur dioxide emissions and most (89%) of tiny particulate matter known as PM10.
The latter can penetrate deep inside the alveoli – the tiny, balloon-like cavities in our lungs where oxygen exchange happens – and do nasty things to our bodies.
In June 2012, the World Health Organisation (WHO) declared that diesel engine fumes can certainly cause cancer, especially lung cancer, in humans. The International Agency for Research on Cancer (IARC), part of WHO, reclassified diesel exhaust to its Group 1 list of substances that have definite links to cancer – thus changing its status to “carcinogen”.
See: 8 July 2012: When Worlds Collide #23: ‘Slow Murder’ by Subsidised Diesel Fumes
So the struggle to reduce sulphur in diesel exhaust emissions is primarily a public health priority even more than an environmental one.
In 2000, the Ministry of Environment gazetted regulations for ambient air, fuel quality and vehicle import standards under the National Environmental Act. The regulation came into effect three years later.
One target under this was to reduce the sulphur content in diesel from 8,000 ppm to 500 ppm between 2000 and 2004. By end 2004, sulphur was brought down to 4,000 ppm, but further progress was not made due to technical issues and lack of funds, Sampath Aravinda Ranasinghe, Environment Management Officer of Air Resource Management Center (AirMAC) at the Ministry of Environment told a recent workshop in Peradeniya.
Sulphur occurs naturally in crude oil, and unless removed during refining process, it will also be in diesel and petrol. The sulphur level in crude oil varies from very low “sweet crude” (around 1,000 to 5,000 ppm) to “sour crude” (around 10,000 ppm to 33,000 ppm).
When refined, sulphur levels in diesel can range between 1,000 ppm to more than 10,000 ppm. If the diesel has not been desulphurized, typical sulphur levels can be between 2,000 and 5,000 ppm. (For petrol, the “natural” sulphur level is much less, between 50 ppm to 1,000 ppm.)
CPC operates the country’s sole oil refinery. According to Ranasinghe, sulphur reduction modification of the existing facility is estimated to cost USD 500 million (LKR 65 billion). The alternative, of expanding and modifying it, will cost around USD 2,000 million (LKR 260 billion).
The cost is substantial, but given diesel’s cancer-causing ability, it is literally a live-saving investment. Studies have found LKR 17 to 22 billion worth of annual health damage costs owing to diesel emissions in Greater Colombo alone, as estimated in a 2006 study by Dr Sunil Chandrasiri of the University of Colombo.
Meanwhile, Prof Ileperuma says: “The technology of removing sulphur from diesel is an involved process and requires another industrial plant and that is why it is expensive. However, the byproduct sulphur can be used to make sulphuric acid (used in industry).”
There are several ways to reduce sulphur in diesel and petrol at a refinery. Experience in developed countries has shown that it is more cost-effective to move directly to the lowest sulphur level (less than 15 ppm), instead of taking incremental steps.
The benefits from lower sulphur levels outweigh the costs in more ways than one. Less sulphur is also better for engine performance, which in turn lowers toxic fumes in the exhaust. Inferior fuel (such as diesel with sulphur content of 1,000 ppm, on the other hand, can reduce the life span of engines by 10 to 20%.
The UN Environment Programme (UNEP) says a significant disadvantage of high-sulphur fuels is that it prevents the use of effective tailpipe emission control technologies.
“For petrol vehicles, 3-way catalysts can still function, but their effectiveness is drastically reduced. For diesel vehicles, high sulphur levels clog and damage devices such as particulate filters, oxidation catalysts or other emission control technologies, making them useless,” says a UNEP guide to low sulphur diesel (see www.unep.org/tnt-unep/toolkit/Actions/Tool10/index.html).
Regulatory and technical issues of cleaning up dirty diesel were discussed at the Stakeholder Dialogue on ‘Development of Fuel Quality and Emission Standards Road: Map for Managing Air Quality in Sri Lanka’ held at the University of Peradeniya on 23 May 2014.
R M Kulasena, Deputy Director of the Central Environmental Authority (CEA) recommended setting up a fuel quality improvement plan, where sulphur content in diesel “should be reduced to at least 1000pmm with immediate effect”.
Fuel quality testing
While fuel quality improvement plan is working, it should also be monitored both by fuel suppliers and independently by third party governmental authorities. This will help control the “infiltration of specific fuels in to country”, he noted.
In his view, the government’s Consumer Affairs Authority (CAA), legally mandated to protect consumer rights, should be authorised to take samples from any fuel product at any location to monitor fuel quality compliance. And if product is found to be below standards, suppliers and distributors should be penalized.
Some fiscal policies are also needed for change. Sri Lanka has been subsidizing diesel prices on the basis that this fuel is used by buses, trains and trucks providing public transport or goods transport. But the subsidy is exploited by the growing number of SUVs and diesel-driven motor cars. This, in effect, is subsidizing a cancer causing agent.
A similar situation is found in most South Asian countries where petrol is highly taxed and part of it cross-subsidises diesel (whereas in China, taxes do not differentiate between petrol and diesel).
Reducing sulphur in Super Diesel is a commendable first step. But much more needs to be done on policy, regulatory and technical fronts before we can breathe easily.
[Note: Sri Lanka will be hosting Better Air Quality 2014 international conference on 19 – 21 November in Colombo. BAQ is the flagship event of Clean Air Asia covering the key sectors of transport, energy, industry and climate change, with a particular emphasis on government policies and measures. This presents an opportunity for clean air advocacy groups to press Sri Lanka government to clean up its own air in decisive ways.]